7th International Macrostomum Meeting November 29 – December 1, 2013 European Research Institute for the Biology of Ageing Groningen, The Netherlands Program, participants, abstracts and general information Organizers: Eugene Berezikov, Lukas Schärer, Peter Ladurner Sponsored by: Stichting Medicorum ERIBA Program Friday, November 29, 2013 16:00‐18:00 Registration 18:00‐19:00 Peter Lansdorp. Guanine‐rich DNA and stem cells 19:00‐ Welcome drinks and dinner at ERIBA Saturday, November 30, 2013 8:30‐9:00 Coffee 9:00‐9.40 Willi Salvenmoser. Microscopic anatomy of Macrostomum lignano 9:40‐10.00 Roland Hoffman. Use of nanotomy for Macrostomum lignano 10.00‐10.30 Kira Zadesenets. The variation in chromosome number in karyotype of free‐ living flatworm, Macrostomum lignano (Platyhelminthes, Turbellaria) 10.30‐11.00 Coffee break 11.00‐11.30 Kaja Wasik. Building molecular genetic tools in a new model organism – Macrostomum lignano 11.30‐12.00 Eugene Berezikov. Macrostomum lignano genomic resources 12.00‐12.30 Jochen Rink. Heads or tails: Polarity in Planarians 12.30‐13.30 Lunch 13.30‐16.30 Free time (sightseeing opportunity, lab tour, collaborator meetings) 16.30‐18.00 Poster session, combined with refreshments and small bites 18.00‐18.30 Walk to a restaurant in a city center 18.30‐ Joint dinner in the restaurant NI HAO (Gedempte Kattendiep 122) 2 Program posters Belinda Artes, Frederic Pacho, Sabrina Folie, Giada Carta, Constanze Ettl, Peter Ladurner. M. lignano projects in brief: TALENS, stem cells, gene complexity, antibodies. Magda Grudniewska, Stijn Mouton and Eugene Berezikov. The flatworm Macrostomum lignano is a powerful model for stem cell and ageing research. Georgina A. Rivera‐Ingraham, U. Bickmeyer, D. Abele. Nitric oxide: a modulator of the hypoxic response in Macrostomum lignano? Stella S. Schukies, Sigmund V. Sperstad and Matthias Leippe. A potential Toll‐like receptor of Macrostomum lignano. Sigmund V. Sperstad and Matthias Leippe. Evolutionary conserved immune effector proteins in Macrostomum lignano. Valeria Vavilova, Irina Sormacheva, Evgeniy Brusentsev, Sergei Amstislavsky, Eugene Berezikov and Alexandr Blinov. Cryopreservation of free‐living flatworm Macrostomum lignano. Jakub J. Wudarski, Daniel Olivieri, Philipp M. Weissert, Eugene Berezikov. Towards transgenesis in Macrostomum lignano 3 Program Sunday, December 1, 2013 9:00‐9:30 Coffee 9:30‐10:00 Steven Ramm. Functional and evolutionary genetics of seminal fluid in Macrostomum 10:00‐10:30 Birgit Lengerer. Fundamentals of biological adhesion in Macrostomum lignano 10:30‐11:00 Robert Pjeta, Julia Wunderer. Posterior end specific genes in Macrostomum lignano 11:00‐11:30 Coffee break 11.30‐12:00 Stijn Mouton. Studying ageing and rejuvenation in Macrostomum lignano 12:00‐12:30 Lukas Schärer. General discussion and closing remarks 12.30‐ Lunch and departure 4 Abstracts Talk: Guanine-rich DNA and stem cells Peter Lansdorp European Research Institute for the Biology of Ageing, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands 5 Abstracts Talk: Microscopic anatomy of Macrostomum lignano Willi Salvenmoser1, Bernhard Egger1, Michael W. Hess2 and Peter Ladurner1 1University of Innsbruck, Institute of Zoology and CMBI, Technikerstrasse 25, A-6020 Innsbruck, Austria 2Division of Histology and Embryology, Innsbruck Medical University, A-6020 Innsbruck, Austria Here we describe the major tissues and cell types of the model organism Macrostomum lignano with light and electron microscopical methods. We will discuss in detail the epidermis with epitheliosomes, lysosomes, Golgi fields and the polymorph structured nucleus; the musculature and their interactions with the extra cellular matrix; a new cell type in the gut; two new cell types in the male gonad and also parenchymal cells types. In addition we will show the protonephridial system, the male copulatory organ and the stem cell system. Furthermore the nervous system and the different gland cell types will be discussed. Finally we will show a comparison between high pressure frozen and chemical fixed animals. 6 Abstracts Talk: Use of nanotomy for Macrostomum lignano Roland Hoffmann European Research Institute for the Biology of Ageing, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands New developments in transmission electron microscopy (TEM) allow large area imaging of Macrostomum lignano at macromolecular resolution. 7 Abstracts Talk: The variation in chromosome number in karyotype of free- living flatworm, Macrostomum lignano (Platyhelminthes, Turbellaria) Kira S. Zadesenets1, Irina D. Sormacheva1, Alexander G. Blinov1, Eugene Berezikov2, Nikolay B. Rubtsov1 1 – Institute of Cytology and Genetics SB RAS, Novosibirsk, Russian Federation 2 - European Research Institute for the Biology of Ageing, Groningen, The Netherlands In this study preliminary results of cytogenetic analysis of chromosomes of M. lignano are presented. Earlier, the karyotype of M. lignano was described as 2n=8 (one pair of large chromosomes and 3 pairs of small chromosomes) (Egger and Ishida, 2005). In this study the cytological analysis was performed for individual worms of DV1 line. The chromosome slide preparation technique was optimized for obtaining metaphase spreads from single worms. It was shown that karyotype of diploid cells in different individuals can contain 8, 9 or 10 chromosomes. In all cases karyotype contained 6 small metaphase chromosomes, but the number of large metaphase chromosomes could vary (1, 2 or 3). The chromosome rearrangement could be explained by chromosomal duplication event which led to tetrasomy 1. In this presentation the chromosome number variability in different individuals of M. lignano is discussed. 8 Abstracts Talk: Building molecular genetic tools in a new model organism – Macrostomum lignano Wasik K.A.1, Battistoni G. 1, Gurtowski J. 1, Schatz M.C. 1, Ladurner P., Schärer L., Berezikov E. 3, Hannon G.J. 1,2 1. Watson School of Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA. 2. Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA. 3. European Research Institute for the Biology of Aging, University Medical Center Groningen, 9700 AD Groningen, The Netherlands Macrostomum lignano has an impressive regenerative ability and presents an interesting opportunity to study stem cells (neoblasts) in detail. However, the molecular tools for manipulating Macrostomum remain limited. Therefore, we sought to develop a minimal set of tools to aid in the study of Macrostomum. First, we have sequenced Macrostomum’s genome and, in collaboration with the Berezikov (ERIBA) and Schatz (CSHL) labs, are currently preparing a draft genome assembly. Additionally, we have sequenced and assembled the transcriptome from whole worms and sorted neoblasts. As an additional layer to the transcriptome, we have sequenced the small RNA populations from whole worms and sorted neoblasts. Finally, we have generated a Macrostomum BAC library consisting of 60,000 20Kb BACs and 40,000 60Kb BACs. The BAC backbone used has been optimized for genomic recombineering and the library should prove useful in the development of transgenic worms. Taken together, these advances should prove an important resource for the Macrostomum community. Macrostomum neoblasts express PIWI proteins, which seem to be crucial for the worms’ regenerative properties. PIWI proteins together with their associated PIWI-interacting-RNAs (piRNAs) are responsible for preventing the mobilization of transposable elements in the germline in many organisms. Genetic ablation of PIWIs or piRNAs in these organisms leads to uncontrolled transposition and sterility. In Macrostomum PIWI proteins appear to play a role outside of their normal germline context. We are interested in studying PIWI proteins in Macrostomum to understand their role in this stem-cell specific context. Towards this goal, we have generated antibodies against 4 presumptive PIWI proteins in Macrostomum (MacPIWIs). These antibodies can be used for immunofluorescence, western blot and immunoprecipitaiton. Using these antibodies, we have observed that MacPIWI1/2 associate with a class of presumptive piRNAs (29-31nt long, 1U bias). We are currently characterizing this piRNA population as well as other small RNA populations. 9 Abstracts Talk: Macrostomum lignano genomic resources Eugene Berezikov European Research Institute for the Biology of Ageing, Groningen, The Netherlands The progress towards integrating transcriptome and genome information and development of genome editing tools for M. lignano will be presented. 10 Abstracts Talk: Heads or tails: Polarity in Planarians Jochen Rink Max Plank Institute of Molecular Cell Biology and Genetics Dresden, Germany The regenerative abilities of planarians present body plan morphogenesis from arbitrary starting points, thus providing a unique experimental system for studying the mechanisms that shape and proportion tissues. Our lab has so far concentrated on the mechanisms patterning the planarian A/P-axis. The striking RNAi phenotypes of beta-Catenin-1/Canonical Wnt signaling pathway components clearly implicate this pathway in A/P-axis patterning, but whether beta-Catenin acts directly as cell fate determinant or indirectly via the selection of other patterning cues has remained unclear. We have examined gene expression patterns under inhibition or overactivation of the pathway and we succeeded in directly measuring